&#34;Improved Design For Stabilizing Fabric Bulk Bags&#34;

ABSTRACT

An improved bulk bag with an upper portion of the sidewalls that is sloped inward from vertical so that when the fabric is stretched upward in the lifting process, thereby creating tension in the vertical fabric, the tension will be maintained after the bag is no longer in a lift position, as the fabric cannot slide back down around the product due to the restricted size of the fabric and such tension provides stronger restrictions to product movement to provide increased stability.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from provisional patent application, entitled “Improved Design for Stabilizing Fabric Bulk Bags,” filed on Nov. 9, 2005, bearing Ser. No. 60/735,642, incorporated herein by reference thereto.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable

REFERENCE TO A “MICROFICHE APPENDIX”

Not applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The apparatus of the present invention relates to fabric bulk bags and more particularly to an improved bulk bag having at least the upper portion of the side walls extending inward from the vertical to allow the material in the bag to stabilize the filled bag.

2. General Background and Description of the Invention

Over the history of the use of bulk bags, one of the greatest issues has been the stabilization of bulk bags being carried on pallets and stacked in warehouses. Historically, bulk bags, when “filled” with product, are never actually full, and would show loose fabric on the top, due to settling of the product. The problem of stabilization was never an issue for bags being carried by the loops because in the suspended condition, there is tension on the side walls to keep the product in a stable position.

However, once the bag is placed on a platform, such as the floor or a wood pallet, there no longer is the side wall tension, and the bag is able to slump and bulge in response to any product movement. This is why one of the most common instructions for filling these fabric bags is start with the bag's bottom corners 2 to 3 inches above the platform. This position automatically applies tension to the side walls and encourages the product into good vertical columns. Once the bag is released, there is no longer anything holding the vertical tension in the side walls and product shaping within the bag is left to the fabric. As long as the fabric stays tightly stretched around the product, the bag's appearance and performance when being handled is good.

However, in all the current designs that this inventor is aware of, the side walls of the bag are dimensionally equal from top to bottom. Therefore, any space at the top of the bag, allows the fabric to slip down the sides of the product columns. This produces extra fabric, which is no longer filled, to be adjacent to the product. This provides product with inertia from movement or transportation to have chance to move and destabilize the bag.

Therefore, there is a need in the industry to provide a bulk bag which when filled, and moved, or lifted, the product in the bag is undisturbed, and when returned to its position, maintains the sidewalls firm, with no sagging or slipping, to allow stability to the bag, and allow other bags to be stacked thereupon.

BRIEF SUMMARY OF THE INVENTION

The improved bag of the present invention addresses this problem in a very simple and straight forward manner. What is provided is an improved bulk bag which includes the design of shrinking the outer dimensions of the bag so that the top of the bag is significantly smaller than the bottom of the bag, by forming one or more darts, as defined herein, either on one or more corners of the bag or along one or more sidewalls. By forming at least a portion of the bag sidewalls to face inwardly from the vertical, there is created a situation whereby the fabric remains in tension at all times. That is, the fabric cannot slip down around the product as the product downwardly adjacent to any portion of fabric is bigger in diameter than the fabric. The product would have to ‘squeeze’ upward to fit into the smaller fabric space.

Therefore, it is a principal object of the present invention to provide a new bag design whereby the bag cannot slip down and create space for movement;

It is a further object of the present invention to provide a bag design whose stability producing tension can be achieved even if the bag is only partially full;

It is a further object of the present invention to provide a bag that will remain stable although a range of product heights is used in a single bag;

It is a further object of the present invention to provide a bag that will remain stable even though product within the bag shifts due to density changes or when a user uses a single bag for multiple products;

It is a further object of the invention to provide a bag whereby although product can shrink and reduce in height, the bag will still provide support as long as the product is maintained inside the bags design that is enlarging as the product shrinks;

It is a further object of the present invention to provide an improved bulk bag that prevents the slumping of sidewalls and product by providing an upper portion of the sidewalls that slopes inward from vertical, with the use of one or more darts, so that the product maintains the fabric in its full vertical position;

It is a further object of the present invention to provide an improved bulk bag with an upper portion of the sidewalls that is sloped inward from vertical so that when the fabric is stretched upward in the lifting process, thereby creating tension in the vertical fabrics, the tension will be maintained after the bag is no longer in a lift position, as the fabric cannot slide back down around the product due to the restricted size of the fabric and such tension provides stronger restrictions to product movement to provide increased stability.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:

FIG. 1 illustrates a side view of a conventional prior art bulk bag filled with product;

FIG. 2 illustrates the filled bulk bag in FIG. 1 being lifted by a forklift;

FIG. 3 illustrates the filled bulk bag in FIG. 2 being returned to its position after being lifted, whereby the vertical sidewalls sag, after time and/or movement, around the product in the bag;

FIG. 4 illustrates an overall view of the new and improved bag of the present invention;

FIG. 4A illustrates an overall view of the improved bag with the darts formed along the sidewalls;

FIG. 5 illustrates a side view of the improved bag of the present invention;

FIG. 6 illustrates an isolated view of the upper end of the improved bag of the present invention;

FIG. 7 illustrates a top view of the improved bag of the present invention;

FIGS. 8 through 11 illustrate variations in the upper end configuration of the bag of the present invention;

FIG. 12 illustrates a representational view of the forces acting on the side walls of the bag of the present invention when filled with bulk;

FIG. 13 illustrates an isolated view of forces acting on the upper portion of the bag of the present invention when containing bulk;

FIG. 14 illustrates an alternate embodiment of the improved bag of the present invention; and

FIG. 15 illustrates two bags of the present invention stacked upon one other filled with bulk.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1 through 3 illustrate a prior art bag, while FIGS. 4 through 15 illustrate the improved bag of the present invention.

Prior to a discussion of the present invention, reference is made to FIGS. 1 through 3, which illustrate a prior art bag 10 and the problems confronted which such a bag 10 when filled with bulk material. As seen in FIG. 1, prior art bag 10 is a conventional bag having vertical sidewalls 12, a top 14, and resting on a base 16. The bag 10 includes four lifting loops 18. In this illustration, the bag 10 is filled with a dry bulk material, which cannot be seen. In FIG. 2, the bag 10 has been lifted by lifting loops 18, by a forklift, for example, so that the base 16 is no longer resting on a surface. The bulk material in the bag 10 would tend to settle within the bag space, in the direction of arrow 15. In FIG. 3, when the bag 10 is returned to rest on its base 18, the vertical sidewalls 12, which have been pulled upward, when lifted, return to their position, because the bulk has settled in the bag, the sidewalls 12 slide downward, and tend to form creases and folds 20, which are very undesirable, especially if other filled bags 10 are placed atop the bag 10 illustrated.

Almost every product moves after being poured into the bag. It densifies (settles) with time or during handling and shipping. The particles are irregularly shaped and the movement allows these particles to lodge closer and closer together, thus reducing the product height. By lifting the bag by the loops after filling, a great percentage of this settling is achieved immediately. At the same time, during the lift, the fabric is stretched and the widest part of the fabric is raised above the maximum amount of product and the maximum amount of the restricted portion of the bag is raised above the product to hold as much tension as possible.

With all of this in mind, there created a need for a bag to be designed to match the product characteristics in a manner that the intended amount of product initially fits into the bag and the settled or densified product is still above a certain point along the sidewalls of the bag, after the required lifting and stretching of the fabric to improve stability. The present invention addresses this need.

The bag of the present invention, as illustrated by the numeral 100 in FIGS. 4 through 15, solves this problem in the art. As seen first in FIG. 4, bag 100, is filled with a bulk material, usually a powder or granular material. As seen bag 100 includes a plurality of side walls 102, extending upward from a base 104, and terminating in a top portion 106. As with most bags, the top 106 includes an opening 108, into which the bulk material is poured into the bag 100, and is closed via an iris fabric closure 110.

Unlike any previous bulk bag known to the inventor, bag 100 includes an improvement which eliminates sagging of the side walls 102, at any time while filled with bulk material. This improvement is illustrated clearly in isolated view in FIG. 6. At each corner 109 of the bag 100, there is formed a dart 112, the dart 112 extending from a point 114 below the upper end of the sidewalls 102, and formed inward along the top 106, which results in each of the upper portion 115 of the four sidewalls 102, from point 114, angulated inward along sew line 107, so as to define a truncated pyramid 118, from point 114 to the top portion 106 of the bag. This can be clearly seen in side view in FIG. 5 and in overall view in FIG. 4.

As an alternative, as illustrated in FIG. 4A, the darts 112 may be formed along at least one, or up to all four sidewalls 102 of the bag 100, terminating at their upper end at top 106, and the same effect would be achieved as having the darts 112 formed on the corners as seen in FIG. 4.

For purposes of definition, a “dart” is defined herein as a line of stitching extending from a point along the sidewall upwards to the top of the bag at an angle so that two or more layers of fabric form the dart, but preferably two layers. The dart may be formed at one or more corners of the bag sidewalls or anywhere along one or more sidewalls between the corners. An example of a dart formed on the corner as defined herein is shown in FIG. 6A, while an example of a dart formed along the sidewall is shown in FIG. 4A.

FIGS. 7 through 11 illustrate the formation of the truncated pyramid 118 having varying heights. FIG. 7 illustrates a top view of the filled bulk bag 100, with the four upper portion sidewalls 115, extending at an angle from the vertical to the top 106. As seen in FIG. 7, the shape of the bag 100 takes on an almost circular shape, when filled with bulk material.

In FIGS. 8 through 10, there is illustrated the bag 100 filled with bulk material 101, to a point 103. In each of the representational drawings, the bulk material 101 is filled to a point above the point 114, i.e. the point at which the dart 112 is formed along each sidewall 102. This fact will be critical and more fully explained. However, for purposes of FIGS. 8 through 10, arrows 130, show the vertical line 131, while arrows 132 illustrate the angulated upper sidewalls 115, when the dart 112 is formed in varying lengths, which define a greater upper truncated pyramid portion 118 on the bag. In FIG. 11, the dart 112 is formed extending from the base 104, extending upward to the top 106, so that in effect each side wall 102 becomes a truncated pyramid 118, while no portion of the sidewall 102 is vertical, unlike the previous embodiments.

As was explained earlier in reference to the prior art bag shown in FIGS. 1 through 3, the improvement as described above, in relation to FIGS. 4 through 11, solves the sagging side wall problem confronted in the art. It has been found through experimentation, that when the side walls 102 are designed to include an upper truncated pyramid portion 118, formed by the darts 112 at each corner, when bulk material is poured into the bag above the lowest point of the angulated wall portions 115, the bulk will stay firm against the bag sidewalls 102, and eliminate sagging or folding of the walls as experienced by all other filled bulk bags.

The experiments show, as illustrated in FIGS. 12 and 13, that the bulk material 101 which is poured above the lowest point of the angulated walls 115, as seen in FIG. 13, for example, the upper portion sidewalls 115 define an area smaller than the lower vertical sidewalls 102. Therefore when the bag 100 is raised and returned to its rest, the angulated sidewalls 115, having a smaller diameter than the lower, vertical sidewalls 102, cannot slide past the upper sidewall space, and therefore are maintained tight, and without any sags or folds. As seen in FIGS. 12 and 13, arrows 146 illustrate the forces within the bag acting outward on the vertical sidewalls 102 and the angulated sidewalls 115. These forces continue to act on the sidewalls when the bag is stationary or being transported, and when the bag is returned to its resting place, the upper sidewalls 115 are unable to travel into the larger space defined by the vertical sidewalls 102, and therefore the bag is maintained erect and with the capacity to have other filled bags stacked upon it. In all cases when this principle is at work is when the bulk material within the bag has been filled to a point above the lowest point of the formation of the angulated sidewalls, which would be point 114, as illustrated in FIG. 13.

FIG. 14 illustrates an embodiment of bag 100, which may be a bag formed by material which when woven, would define a bag having vertical sidewalls 102 to a certain point, and then the weave would define the smaller upper truncated portion 118 of the bag. That is, rather than darts 112 being sewn in the bag to achieve the smaller truncated upper portion 118, the weave of the fabric would define this feature.

As seen in FIG. 15, there is illustrated a first lower bag 100 filled with bulk, with a second bulk bag 100, also filled with bulk, resting atop lower bag 100. As seen in this figure, the particular bulk bag being utilized with the present invention is a “pot-bellied” bulk bag, of the type having a pair of channels 150, each housing a rigid insert 152, therein, the channels spaced apart to receive the tynes of a forklift. The channels are secured to a pot-bellied portion 154, filled with bulk, between the channels to define a firm and rigid base 156 of each of the bags, which allows ease in stacking. This base feature combined with the present invention insures bags which can be stacked safely and securely, without risking loss of firmness in the sidewalls of the bags.

Likewise, this new design can probably be used to modify any existing design such as circular woven, u-panel, one piece bags, baffle bags, Portabulk, etc.

All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise.

PARTS LIST

Part Number Description 10 prior art bag 12 side walls 14 top 15 arrow 16 base 18 lifting loops 20 folds 100 bag 101 bulk material 102 side walls 103 point 104 base 106 top portion 107 sew line 108 opening 109 corner 110 fabric closure 112 dart 114 point 115 side walls 118 truncated pyramid 130 arrows 131 vertical line 132 arrows 146 arrows 150 channels 152 rigid insert 154 pot belly portion 156 rigid base

The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims. 

1. An improved fabric bulk bag of the type having sidewalls, whereby a dart is formed along an upper portion of at least one of the sidewalls to define an area of a reduced diameter than the portion of the bag sidewalls below the dart, so that when product is placed into the bag to a point above the lower portion of the dart formed in the bag sidewalls, the portion of the sidewalls below the dart are maintained in tension, which provides for a more stable bag which is capable of supporting itself and other filled bags positioned thereupon.
 2. The bulk bag in claim 1, wherein the darts formed on the sidewalls may be angled from the bottom portion to the top portion.
 3. The bulk bag in claim 1, wherein the angled portion of the bag, defined by the dart, commences on the sidewall around 14 to 15 inches from the top of the bag and terminates at a point around 5 inches from vertical along the horizontal top of the bag.
 4. The bulk bag in claim 1, wherein as pressure is applied from above by a second bag stacked on top of a first bag, the pressure meets the floor and then turns 90 degrees toward the side walls of the bag, defining a redirection of pressure through out the entire bag, including the angled portion of the bag.
 5. The bulk bag in claim 1, wherein there would be provided one or more darts at at least one or more corners of the bag.
 6. The bulk bag in claim 1, wherein there would be provided one or more darts along at least one or more sidewalls of the bag.
 7. An improved bulk bag of the type having sidewalls, whereby one or more darts on the upper portion of the bag sidewalls define an area a reduced diameter than the lower portion of the bag sidewalls, so that when product is placed into the bag to a point above the lower portion of the bag sidewalls, the sidewalls are maintained in tension, which provides for a more stable bag which is capable of supporting itself and other filled bags positioned thereupon.
 8. An improved fabric bulk bag design which allows more stable stacking of multiple bags filled with product, the bag comprising: a. sidewalls, a top portion and a bottom portion, all defining a bulk space therewithin; b. a lower portion of the sidewalls extending vertically upward from the bottom portion; c. a dart formed on at least an upper portion of the sidewalls from the vertical lower portion of the sidewalls, so as to define an angled truncated top portion of the bag; d. the product contained within the bag to a point above the lowest point of the dart, which results in the entire sidewalls remaining in tension.
 9. The improved bag design in claim 8, wherein when the side directed pressure hits the angled portion of the bag, caused by product within the bag, or another filled bag stacked upon it, there is provided a lift which stabilizes the lower bag.
 10. The improved bag design in claim 8, wherein the dart in the sidewalls define a means for maintaining the fabric of the sidewalls in tension at all times, preventing the fabric from slipping down around the product in the bag.
 11. The improved bag design in claim 8, wherein the darts formed in the sidewalls define an upper surface when filled with product capable of supporting another filled bag thereupon.
 12. An improved bulk bag of the type having sidewalls, which provides for a more stable bag which is capable of supporting itself and other filled bags positioned thereupon, which comprises an upper portion of the bag sidewalls having a dart formed therein so as to define a reduced circumference of the filled bag at the darts, so that when product is placed into the bag to a point above the darts, the sidewalls are maintained in tension.
 13. An improved fabric bulk bag, comprising: a. sidewalls, a top portion and a bottom portion, all defining a bulk space therewithin; b. a lower portion of the sidewalls being substantially vertical; c. an upper portion of the sidewalls having a dart in place, which defines that portion of the sidewall formed inwardly from the vertical portion of the sidewalls, so that when product is poured into the bag at least to a level above the lowest point of the dart, the lower portion of the sidewalls remain vertical and rigid when placed on a surface or when other filled bags are stacked thereupon.
 14. An improved bulk bag with an upper portion of the sidewalls that is sloped inward from vertical defining a reduced area of the bag sidewalls, so that when the sidewall fabric is stretched upward in the lifting process, creating tension in the vertical fabric, tension will be maintained as the fabric in the reduced area cannot slide back down around the product due to the reduced area of the fabric compared to the product surface area.
 15. The improved bulk bag in claim 14, wherein the upper portion of the sidewalls are sloped inward as a result of one or more darts formed in the upper portion of the sidewalls so that the product maintains the fabric in its full vertical position when the bag contains product to a level at least above the lowest point of the one or more darts.
 16. The improved bulk bag in claim 15, wherein one or more of the darts may be formed at the corners of the bulk bag or along the sidewalls of the bulk bag.
 17. An improved bulk bag with an upper portion of the sidewalls that is sloped inward from the vertical so that when the fabric is stretched upward in the lifting process, thereby creating tension in the vertical fabrics, that at least a portion of the tension will be maintained as the fabric cannot slide back down around the product due to the restricted size of the fabric.
 18. The improved bulk bag in claim 17, wherein the upper portion of the sidewalls are sloped inward by the use of one or more darts formed at one or more corners or along one or more sidewalls of the bag to provide increased stability.
 19. The improved bulk bag in claim 18, wherein the darts define a means to create tension in the vertical fabrics when the filled bag is lifted, so that at least a portion of the tension will be maintained after the bag is no longer in a lift position, as the fabric cannot slide back down around the product due to the restricted size of the fabric and such tension provides stronger restrictions to product movement to provide increased stability.
 20. An improved fabric bulk bag design which allows more stable stacking of multiple bags filled with product, the bag comprising: a. sidewalls, a top portion and a bottom portion, all defining a bulk space therewithin; b. at least an upper portion of the sidewalls formed inwardly from the vertical by the use of one or more darts along the sidewalls, so as to define an angled truncated top portion of the bag; c. wherein as pressure is applied from above by a second bag stacked on top of a first bag, the pressure meets the floor and then turns 90 degrees toward the side walls of the bag, defining a redirection of pressure through out the entire bag, including the angled portion of the bag. 